The leukotrienes constitute a group of locally acting hormones, produced in living systems from arachidonic acid. The major leukotrienes are Leukotriene B.sub.4 (abbreviated as LTB.sub.4), LTC.sub.4, LTD.sub.4 and LTE.sub.4. The biosynthesis of these leukotrienes begins with the action of the enzyme 5-lipoxygenase on arachidonic acid to produce the epoxide known as Leukotriene A.sub.4 (LTA.sub.4), which is converted to the other leukotrienes by subsequent enzymatic steps. Further details of the biosynthesis as well as the metabolism of the leukotrienes are to be found in the book Leukotrienes and Lipoxygenases, ed. J. Rokach, Elsevier, Amsterdam (1989). The actions of the leukotrienes in living systems and their contribution to various diseases states are also discussed in the book by Rokach.
EP 385,662 (published Sep. 5, 1990) discloses 5-lipoxygenase inhibitors of the formula ##STR2## in which a heterocyclic moiety, Q, is linked to Ar, which may be phenylene, via A--X. The group attached to Ar represents a tertiary alcohol substituted O-, S- or N-containing heterocyclic ring, whereas the corresponding moiety in the present invention is a aromatic group. The Ar.sup.4 unit of the present invention is absent from the above formula.
WO94/00444 (published Jan. 6, 1994) discloses leukotriene biosynthesis inhibitors which are aryl substituted naphthalenes of the formula ##STR3##
The present compounds differ from those of the above formula in that instead of the ring containing X.sup.1 and X.sup.2, they possess an aromatic ring.
Crawley et al., (J. Med. Chem., 1992, 35, 2600-2609) discloses the 5-lipoxygenase inhibitor of the formula below. The compounds of the present invention differ in that they lack the tetrahydropyran ring, and that they possess an aromatic substituent on both the monocyclic and bicyclic ring moieties. ##STR4##